Commit Graph

4 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo c351c28161 perf diff: Use perf_session__fprintf_hists just like 'perf record'
That means that almost everything you can do with 'perf report'
can be done with 'perf diff', for instance:

$ perf record -f find / > /dev/null
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.062 MB perf.data (~2699
samples) ] $ perf record -f find / > /dev/null
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.062 MB perf.data (~2687
samples) ] perf diff | head -8
     9.02%     +1.00%     find  libc-2.10.1.so               [.] _IO_vfprintf_internal
     2.91%     -1.00%     find  [kernel]                     [k] __kmalloc
     2.85%     -1.00%     find  [kernel]                     [k] ext4_htree_store_dirent
     1.99%     -1.00%     find  [kernel]                     [k] _atomic_dec_and_lock
     2.44%                find  [kernel]                     [k] half_md4_transform
$

So if you want to zoom into libc:

$ perf diff --dsos libc-2.10.1.so | head -8
    37.34%                find  [.] _IO_vfprintf_internal
    10.34%                find  [.] __GI_memmove
     8.25%     +2.00%     find  [.] _int_malloc
     5.07%     -1.00%     find  [.] __GI_mempcpy
     7.62%     +2.00%     find  [.] _int_free
$

And if there were multiple commands using libc, it is also
possible to aggregate them all by using --sort symbol:

$ perf diff --dsos libc-2.10.1.so --sort symbol | head -8
    37.34%             [.] _IO_vfprintf_internal
    10.34%             [.] __GI_memmove
     8.25%     +2.00%  [.] _int_malloc
     5.07%     -1.00%  [.] __GI_mempcpy
     7.62%     +2.00%  [.] _int_free
$

The displacement column now is off by default, to use it:

perf diff -m --dsos libc-2.10.1.so --sort symbol | head -8
    37.34%                   [.] _IO_vfprintf_internal
    10.34%                   [.] __GI_memmove
     8.25%     +2.00%        [.] _int_malloc
     5.07%     -1.00%    +2  [.] __GI_mempcpy
     7.62%     +2.00%    -1  [.] _int_free
$

Using -t/--field-separator can be used for scripting:

$ perf diff -t, -m --dsos libc-2.10.1.so --sort symbol | head -8
37.34, , ,[.] _IO_vfprintf_internal
10.34, , ,[.] __GI_memmove
8.25,+2.00%, ,[.] _int_malloc
5.07,-1.00%,  +2,[.] __GI_mempcpy
7.62,+2.00%,  -1,[.] _int_free
6.99,+1.00%,  -1,[.] _IO_new_file_xsputn
1.89,-2.00%,  +4,[.] __readdir64
$

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260978567-550-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-16 16:53:37 +01:00
Arnaldo Carvalho de Melo cdccc69003 perf diff: Fix documentation
Add a newline do fix this problem:

ERROR: perf-diff.txt: line 31: closing [blockdef-listing]
delimiter expected

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1260882082-10007-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-15 15:28:04 +01:00
Ingo Molnar d30531c672 perf diff: Improve the help text
Fix the short line displayed by 'perf' and also fix some other
details in the longer text.

Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-15 15:26:18 +01:00
Arnaldo Carvalho de Melo 86a9eee047 perf diff: Introduce tool to show performance difference
I guess it is enough to show some examples:

[root@doppio linux-2.6-tip]# rm -f perf.data*
[root@doppio linux-2.6-tip]# ls -la perf.data*
ls: cannot access perf.data*: No such file or directory
[root@doppio linux-2.6-tip]# perf record -f find / > /dev/null
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.062 MB perf.data (~2699 samples) ]
[root@doppio linux-2.6-tip]# ls -la perf.data*
-rw------- 1 root root 74440 2009-12-14 20:03 perf.data
[root@doppio linux-2.6-tip]# perf record -f find / > /dev/null
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.062 MB perf.data (~2692 samples) ]
[root@doppio linux-2.6-tip]# ls -la perf.data*
-rw------- 1 root root 74280 2009-12-14 20:03 perf.data
-rw------- 1 root root 74440 2009-12-14 20:03 perf.data.old
[root@doppio linux-2.6-tip]# perf diff | head -5
   1        -34994580     /lib64/libc-2.10.1.so   _IO_vfprintf_internal
   2        -15307806         [kernel.kallsyms]   __kmalloc
   3    +1   +3665941     /lib64/libc-2.10.1.so   __GI_memmove
   4    +4  +23508995     /lib64/libc-2.10.1.so   _int_malloc
   5    +7  +38538813         [kernel.kallsyms]   __d_lookup
[root@doppio linux-2.6-tip]# perf diff -p | head -5
   1        +1.00%     /lib64/libc-2.10.1.so   _IO_vfprintf_internal
   2                       [kernel.kallsyms]   __kmalloc
   3    +1             /lib64/libc-2.10.1.so   __GI_memmove
   4    +4             /lib64/libc-2.10.1.so   _int_malloc
   5    +7  -1.00%         [kernel.kallsyms]   __d_lookup
[root@doppio linux-2.6-tip]# perf diff -v | head -5
   1        361449551 326454971 -34994580     /lib64/libc-2.10.1.so   _IO_vfprintf_internal
   2        151009241 135701435 -15307806         [kernel.kallsyms]   __kmalloc
   3    +1  101805328 105471269  +3665941     /lib64/libc-2.10.1.so   __GI_memmove
   4    +4   78041440 101550435 +23508995     /lib64/libc-2.10.1.so   _int_malloc
   5    +7   59536172  98074985 +38538813         [kernel.kallsyms]   __d_lookup
[root@doppio linux-2.6-tip]# perf diff -vp | head -5
   1        9.00% 8.00% +1.00%     /lib64/libc-2.10.1.so   _IO_vfprintf_internal
   2        3.00% 3.00%                [kernel.kallsyms]   __kmalloc
   3    +1  2.00% 2.00%            /lib64/libc-2.10.1.so   __GI_memmove
   4    +4  2.00% 2.00%            /lib64/libc-2.10.1.so   _int_malloc
   5    +7  1.00% 2.00% -1.00%         [kernel.kallsyms]   __d_lookup
[root@doppio linux-2.6-tip]#

This should be enough for diffs where the system is non
volatile, i.e. when one doesn't updates binaries.

For volatile environments, stay tuned for the next perf tool
feature: a buildid cache populated by 'perf record', managed by
'perf buildid-cache' a-la ccache, and used by all the report
tools.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
LKML-Reference: <1260828571-3613-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-12-15 08:50:29 +01:00